This invention relates to systems for supplying supplemental oxygen to a patient intermittently with the supply on for a predetermined time interval extending over a plurality of respiratory cycles and the supply off for a plurality of respiratory cycles, where the on and off times are preset based upon prior measurements of the patient's oxygen requirements.
The rate of disability from chronic obstructive lung disease (C.O.L.D.) has been increasing. Such patients have inadequate pulmonary gas exchange resulting in inadequate oxygenation of blood as it passes through the lungs. Inadequate oxygenation of the blood, and thereby the body tissues accounts for the disabling effects of the disease. It has been demonstrated, that continuous administration of supplemental oxygen by nasal cannula overcomes the functional disability and greatly improves the quality of life as well as prolonging life. It is now common practice for ambulatory patients to carry a liquid oxygen cannister supply which weighs nine pounds and lasts approximately 3-4 hours. A usual oxygen supply costs hundreds of dollars a month.